The London Olympics and Paralympics may have caused a dip in foreign visitors coming to Britain yet those who did come spent more than usual, figures suggested on Thursday.

The Office for National Statistics said 3 million came during August, a 5% fall on the same month in 2011, but spending including Games tickets bought before or during their visit was 9% up, an all-time monthly record of £2.38bn being injected into the UK economy.

Businesses and tourist attractions blamed falling trade during London 2012, saying predictions of overcrowding and travel chaos had put off visitors. There was also no mass exodus of Britons on holidays abroad during August, the 7.3m trips outside the UK was about the same as the previous year.

During July and August an estimated 590,000 visitors indicated that they had come to the UK to either attend a ticketed event, participate or work at the Games. These visitors spent about £760m while in the country, on average spending £1,290, almost double what visitors would normally spend, according to the national tourist agency VisitBritain, which said it had expected a drop in numbers.

Sanie Dawe, its chief executive, said: "The extraordinary exposure Britain received during the Games has provided us with an ideal platform to remind people around the world why a visit to Britain is a must, and we are working hard to deliver a strong finish to the year."

Figures overall for the first eight months of 2012 showed similar numbers of visitors to the UK to last year. Their spending was 3% up.

Howard Archer, an economist for analysts IHS Global Insight, told Reuters news agency the weakness in the global economy might have also been a reason for the fall in tourist numbers.

"While the impact of the Olympic Games and the Paralympics on the number of overseas visitors coming to the UK in August may be open to differing interpretations, it is evident that the Games did boost spending by overseas visitors to the UK," he said.